1. Field of the Invention
The present invention relates to customer bridges used at the site of customers of telecommunication networks and more particularly to customer bridges that allow customers to quickly determine the origin of any malfunction in the wiring connected to the customer bridges.
2. Description of the Related Art
Customer bridges are devices that are used to demarcate a customer's equipment and a telecommunications network. The customer bridge is part of a telecommunications system and is connected directly to customer equipment and to the telecommunications network. The customer bridge has network terminals on its network side and customer terminals on its customer side. A network line (e.g., twisted pair of wires) is connected to the network side of the customer bridge which electrically couples the network line to the customer terminals which typically have customer equipment (e.g., telephone, facsimile machine, modem) connected thereto.
At a customer's site such as buildings with multiple customers, a plurality of customer bridges are usually disposed in a housing commonly referred to as network interface unit typically mounted in a basement or in an outdoor environment with the network side of each bridge being connected to an individual network line. Network interface units also include other equipment such as protection circuitry used to prevent customer equipment from being damaged by voltage or current surges.
FIG. 1 depicts a prior art customer bridge 10 that includes a base member 12 which is typically made of plastic. At the customer side of the bridge, a pair of hollow cylindrical projections 14 and 16, typically molded from the same plastic of base member 12 and integral therewith contain electrical terminals which include posts 18 and 20 to which customer terminals 22 and 24 are electrically connected. The posts 18 and 20 extend to and through the bottom of base member 12. Wrapped around posts 18 and 20 are wires 26 and 28 respectively, which over most of their length are protected by sheath, 30. Wires 26 and 28 terminate in a standard well known RJ11 plug, 32. Plug 32 is shown inserted within base member 12 that contains an RJ11 plug mating member (not shown in FIG. 1; see FIG. 2) to which insulated wires 34 and 36 are connected. Thus, each insulated wire 34 and 36 is electrically connected to customer terminals 22 and 24 respectively when plug 32 is properly engaged to the RJ11 plug mating member (not shown) disposed within base member 12.
FIG. 2 shows a cross sectional view of the customer bridge 10 of FIG. 1. Mating member 38 is positioned within base member 12 so that its electrical contacts (not shown) engage with the electrical contacts (not shown) of plug 32. Insulated wires 34 and 36 emanating from mating member 38 are connected to the telecommunications network. Electrical wires 40 and 42 shown connected to customer terminals 22 and 24 provide the electrical connection to a customer device (not shown) such as a telephone, facsimile machine, modem and the like. Customer terminals 22 and 24 make electrical contact with top ends of terminals 44 and 46. The bottom ends of terminals 44 and 46 include posts 18 and 20 that extend beyond the bottom of base member 12.
Many times, a malfunction occurs in a network line and there is a need to determine whether the malfunction is located at the customer side or at the network side of the telecommunications system. In such circumstances, a customer unplugs RJ11 plug 32 electrically disconnecting the network side of the bridge from the customer side. The customer typically plugs into the customer bridge a working telephone handset to test the network line. Thus, for example, if a telephone handset is plugged in and the customer detects a dial tone and is able to dial a number and establish a connection, then it is reasonable to conclude that the problem lies with the customer's wiring and not with the network line. However, plugs such as RJ11 plugs are expensive and many times unreliable in outdoor environments where customer bridges are often located. Thus, many times a malfunction may be due to an inoperative RJ11 plug. Further, the use of a telephone handset or other telecommunications device to test a network line is often laborious and awkward as many times the customer has to go to a basement or to an outdoor location with a telephone, locate the line in question, disconnect the appropriate RJ11 plug and plug in its place a telephone.